The present disclosure relates to a robot according to the main claim, for example a painting robot for painting motor vehicle body components.
Conventional painting robots typically may have a plurality of robot elements swivelable and rotatable relative to each other, which are located kinematically one behind the other, and which guide a rotary atomizer as an application device, for example, wherein the rotary atomizer is supplied by a plurality of supply lines, for example with paint, flushing agent, driving air and high voltage power. A problem in this configuration is the guidance of the supply lines in the individual robot elements, since a change in the position of the robot leads to a respective change in the required length of the line. Therefore on the well-known painting robots the supply lines are guided as a bundle by a swivel joint wherein the bundle is fixed kinematically in front of and behind the swivel joint axially by strain reliefs. The length compensation required for a change in the position of the robot is exclusively achieved by a visible compensation loop placed between the strain reliefs.
A disadvantage of the conventional line guidance as described above for a painting robot is first of all the fact that a compensation loop placed between the strain reliefs is needed in order to achieve the length compensation required for a robot movement, whereby the supply line is unnecessarily long which is disadvantageous with regard to costs, weight, losses of paint and the pneumatic control times.
A further disadvantage of the compensation loop needed for the length compensation is the relatively large space needed by the compensation loop which generally projects out over the outer contour of the multi-element robot arm and therefore limits the freedom of movement of the painting robot.
Furthermore the manufacturing costs and the assembly time for the conventional painting robot described above are relatively large since numerous axial strain reliefs are needed for the supply lines and must be assembled in a way which requires much time and costs.
A further disadvantage of the conventional line guidance of the supply lines for a painting robot arises from the fact that the painting robot usually also allows a rotary movement around a substantially vertical rotary axis, wherein the supply line is loaded with torsion. The axial strain relief reduces the free hose length of the supply line on which the arising torsional load must be taken up. Therefore the axial strain reliefs on the conventional line guidance lead to an increase in the loading by torsion so that additional hose lengths must be kept ready to take up the torsional load arising.
There is, furthermore, another disadvantage with the conventional line guidance on painting robots is that the supply lines cannot be guided in a hose guidance plane whereby use of pigable supply hoses is impeded.
It is, furthermore, disadvantageous to have the additional mechanical loading of the supply hoses used and the associated screw connections as well as the increased time and costs required for assembly and disassembly work with regard to hose mounting or hose changing. Furthermore special components are usually needed for the conventional line guidance which is also disadvantageous.
Accordingly, there is a need for a painting robot with a corresponding improved line guidance for the supply lines.